What is the role of a firewall in cybersecurity?

A firewall plays a critical role in cybersecurity by acting as a barrier between a trusted internal network and untrusted external networks, such as the internet. Its primary function is to filter and monitor both incoming and outgoing network traffic based on predetermined security rules. This means it can allow or block data packets based on source IP address, destination IP address, protocols, and port numbers, thereby protecting the network from unauthorized access, cyber attacks, and various types of malicious traffic.

By effectively managing the flow of traffic, firewalls help enforce security policies and can alert administrators to potential security breaches. They are essential components of network security architecture that help organizations safeguard sensitive data and maintain the integrity of their network. Other options mentioned, like encrypting sensitive data, removing viruses from files, or improving data access speed, address different aspects of cybersecurity and network management but do not encapsulate the primary purpose of a firewall as accurately.